The present invention relates to an improvement for a manipulator and aims at minimizing the size of the part which acts as a wrist of a hand and at enhancing the reliability thereof.
Manipulators of a robot type or a fixed type have been utilized widely in operation in adverse environments, for handling dangerous objects, or in places too small for operators to conduct work, and they have been used for refined and complicated work.
In the structure of such a manipulator, the part which corresponds to the wrist of a human arm is driven to rotate or flex by an actuator provided within a body, of the device; however, as the driving mechanism for a hand equivalent, or more particularly the part which acts as fingers should be positioned ahead of the wrist member, the size of the wrist member unavoidably increases to the level where it is difficult to be inserted into a narrow part, thereby restricting the scope of application.
There has been proposed an arrangement where flexible wires or ropes are wired through the arm or wrist so as to drive the hand equivalent from inside the body; they have been found deterimental in reliability because proper operation can not be secured due to the expansion or sag of the wire or rope or they tend to become torn or worn easily. This may lead to accidents.